This invention relates to a metal gasket for a cylinder head of an internal combustion engine and more particularly to a metal gasket suitable for an engine whose cylinder bores are closely adjacent to each other.
FIGS. 1-3 illustrate one example of a hitherto used metal gasket, wherein a metal gasket is made of a spring steel plate 1 as a blank material and is formed with head 3 along circumferences of cylinder bores 2 and with apertures 4 for bolts.
With such a metal gasket, the beads 3 extend in the same directions as shown in FIG. 3. In case of the cylinder bores 2 closely adjacent to each other, therefore, the adjacent beads 3 are not smoothly connected at a connection 5 which is sharply bent as shown in FIG. 3. Accordingly, it is generally difficult to form the sharply bent connection 5. Moreover, when the gasket is firmly clamped between a cylinder head and an engine cylinder, cracks or permanent deformation would often occur in the connection 5, due to its sharp bent portion, so that the cracked or deformed portions of the gasket do not return to original positions. As a result, sealing performance of the gasket is lowered in the proximity of the connection 5.